US7525110B2 - Multiple irradiation effect-corrected dose determination technique for charged particle beam lithography - Google Patents
Multiple irradiation effect-corrected dose determination technique for charged particle beam lithography Download PDFInfo
- Publication number
- US7525110B2 US7525110B2 US11/671,789 US67178907A US7525110B2 US 7525110 B2 US7525110 B2 US 7525110B2 US 67178907 A US67178907 A US 67178907A US 7525110 B2 US7525110 B2 US 7525110B2
- Authority
- US
- United States
- Prior art keywords
- corrected dose
- proximity effect
- correction
- dose
- fog
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active, expires
Links
Images
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
- G03F7/7055—Exposure light control in all parts of the microlithographic apparatus, e.g. pulse length control or light interruption
- G03F7/70558—Dose control, i.e. achievement of a desired dose
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/30—Electron-beam or ion-beam tubes for localised treatment of objects
- H01J37/317—Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation
- H01J37/3174—Particle-beam lithography, e.g. electron beam lithography
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y10/00—Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
- G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
- G03F7/70—Microphotolithographic exposure; Apparatus therefor
- G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
- G03F7/70491—Information management, e.g. software; Active and passive control, e.g. details of controlling exposure processes or exposure tool monitoring processes
Definitions
- the present invention relates generally to energy radiation lithography technologies and, more particularly, to a technique for numerical determination of an optimal, exposure dose to correct multiple irradiation effect of a charged particle beam which occurs when an ultra-fine pattern is drawn or “written” on a workpiece. Electrons injected into resist on a workpiece (ex. mask substrate) are reflected in the mask substrate and expose resist again. This causes CD deviation and is called proximity effect. The reflected electrons are reflected at a ceiling of writing chamber and expose resist on the mask again. This also causes CD deviation and is called fogging effect. These two phenomena are called multiple irradiation effect in this specification.
- This invention also relates to an integrated circuit pattern writing lithographic apparatus and methodology using the beam dose correction technique.
- variable-shaped electron beam lithography apparatus is typically made up of a movable stage or “table” structure which supports thereon a target object such as a workpiece to be processed, and a scanning electron beam pattern generator unit including an electron optics.
- This optics includes an electron beam source, a couple of spaced-apart beam-shaping aperture plates (also known as “blankers”), and more than one deflector coil operatively associated therewith.
- Each aperture plate has a rectangular opening or hole as formed therein.
- An electron beam emitted from the source first passes through the hole of the upper aperture plate and is then deflected by the deflector to reach the hole of the lower aperture plate.
- the beam is variable-shaped in cross-section and is then irradiated or “shot” onto the surface of a workpiece placed on the stage.
- a further size variation factor is what is called the loading effect, which takes place during etching processes to be done after having drawn a circuit pattern. This arises from inherent differences in density of line segments of the circuit pattern. Specifically, this phenomenon is such that when the patterned resist film is used as a mask is to etch its underlying light shield film, this film experiences unwanted size variations.
- the loading effect-caused size variations also affect the circuit pattern accuracy.
- One ordinary approach to avoiding such pattern size variations occurring due to the proximity effect and the fogging effect is to adjust and control the dose of a pattern writing beam in such a way as to “absorb” them. More specifically, a high-speed/high-performance computer is used to calculate an optimal dose of such beam. Then irradiate the workpiece with the charged particle beam at this corrected dose to thereby write a circuit pattern.
- the corrected beam dose Dp After having input the image data of an original pattern to be written, calculate a proximity effect-corrected dose and a fogging-corrected dose, respectively.
- the calculation of these corrected dose values is performed by a method having the steps of subdividing the workpiece's pattern write area into a matrix of rows and columns of small rectangular tile-like regions, called the “mesh” regions, and solving a prespecified integral equation on a per-mesh basis. Respective corrected doses thus calculated are combined together to obtain a “final” corrected dose. Then, beam control is done so that the beam falls onto the workpiece surface at this dose.
- a specific mathematical formula which defines the absorption amount E of a resist film material concerning the fog effect.
- This formula contains in its integration term a mask surface position-dependent Df(x,y) value. If this Df value within integration is deemed to be constant, the resultant computing equation is simplified. This equation suggests that in order to obtain the intended fog-corrected dose, it is a must to repeatedly execute again and again similar integral calculations over the whole area of the fogging effect's influence range. This will be readily understandable by recalling the fact that the fogging phenomenon per se never exists independently and that the fogging is originated from the behavior of back-scatted electrons produced by the proximity effect. As previously stated, the fogging is much greater in influence range than the proximity effect.
- One way of shortening the calculation time is to presume, when calculating the fog-corrected dose Df, that the proximity effect-corrected dose Dp stays constant within its integration region.
- the proximity effect-corrected dose Dp involved therein is adventurously fixed to a constant value, thereby to noticeably simplify the calculation equation required.
- this presumption namely, “proximity effect constancy” approximation—to calculate the value Df per mesh region with its size of 1 millimeter (mm) as an example, the resulting computation task amount is appreciably lessened, resulting in a substantive decrease in processing time. This enables achievement of high-speed pattern writing.
- a new and improved charged-particle beam lithographic apparatus employing a multiple irradiation effect correction technique unique to the invention.
- This apparatus is generally made up of a pattern writing unit and a control unit operatively connected to the pattern writing unit.
- the writing unit has a radiation source for emitting an energy beam and a beam column operative as a beam pattern generator for deflecting the beam to opportunistically adjust traveling thereof to thereby form a prespecified circuit pattern image on a workpiece.
- the control unit includes a device for correcting the proximity and fogging effects occurrable during pattern imaging using the beam.
- This correction device includes a first calculator which calculates a proximity effect-corrected dose for correction of the proximity effect, a functional module for calculation of a fog-corrected dose for correction of the fogging effect while including therein the influence of the proximity effect, a combiner or multiplier responsive to receipt of the calculated doses for combining them together to thereby numerically determine a total corrected dose and for generating at its output a signal indicative of the total corrected dose, and a beam controller responsive to receipt of the output signal for using the total corrected dose to provide a beam control signal for transmission to the beam column.
- the functional module is arranged including a second calculator unit for calculation of a variable real value indicating the influence of the proximity effect to be taken into account during the fog correction, and a third calculator unit operatively associated with the second calculator unit for using the variable value of the proximity effect to thereby calculate the fog-corrected dose.
- a method for beam dose correction adaptable for use in lithographic systems for writing a pattern on a target workpiece by use of a beam of energy radiation includes the steps of calculating a proximity effect-corrected dose for correction of a proximity effect occurrable during pattern writing, calculating a fog-corrected dose for correction of a fogging effect occurring during the pattern writing using the beam while including influence of the proximity effect, determining a total corrected dose by combining together the doses calculated, and controlling the beam based on the total corrected dose.
- the step of calculating a fog-corrected dose includes a first substep of calculating a variable real value indicative of influence of the proximity effect to be taken into account during fog correction, and a second substep of using the variable value of the proximity effect to calculate the fog-corrected dose.
- the proximity/fogging effect correction technique incorporating the principles of the invention may be arranged by a hardware-based configuration including electrical and/or electronic circuits.
- the principal functionality thereof is implementable by using a computer-executable software program or programs, a firmware-based arrangement, or any possible combinations of more than two of the hardware, software and firmware configurations.
- FIG. 1 is a diagram showing schematically an entire configuration of a variable-shaped electron beam pattern microlithographic apparatus in accordance with one embodiment of this invention.
- FIG. 2 is a pictorial representation of an electron optics employable in the lithography apparatus of FIG. 1 .
- FIG. 3 is a flow diagram of major processes of a beam dose correcting method for use in the apparatus shown in FIG. 1 .
- FIG. 4 is a graph showing, based on actual measurements, a plot of fogging correction error versus mesh size for each of equally spaced line-and-space (L/S) patterns with different mesh sizes for proximity effect correction.
- FIG. 5 is a graph showing, based on measurements, fogging-effect correction errors at varying pattern linewidth values.
- FIG. 6 graphically shows based on measurements fog correct errors vs. order of fog-corrected dose, i.e., correction term order for some typical pattern linewidths.
- FIG. 7 illustrates, in block diagram form, an entire configuration of an electron beam microlithographic apparatus in accordance with another embodiment of the invention.
- FIG. 8 is a flowchart of major processes of a beam dose correction method as used in the apparatus of FIG. 7 .
- FIG. 1 A variable-shaped electron beam lithography (EBL) apparatus embodying the invention is shown in FIG. 1 in the form of a block diagram of some major components thereof. As shown herein, this EBL apparatus is entirely indicated by reference numeral 10 .
- EBL tool 10 is generally made up of a circuit pattern drawing or “writing” unit 12 and a control unit 14 operatively associated therewith.
- the pattern write unit 12 includes a tower-like outer housing structure 16 , called an electron lens barrel, and a processing chamber 18 .
- the electron lens barrel 16 has a scanning electron beam pattern generation unit as built therein.
- This pattern generator is constituted from a variable-shaped electron beam column, which includes an electron gun assembly 20 , a blanking deflection coil 22 , and a blanking aperture plate 24 .
- a table-like structure 36 is situated which is movable in two orthogonal axes that define a horizontal plane, i.e., X coordinate axis and Y coordinate axis.
- the table 26 will be referred to as “XY stage” hereinafter.
- This XY stage 26 supports on its top surface a workpiece 28 under pattern writing and is driven by a known actuator (not shown) to move continuously or discontinuously.
- the workpiece 28 include, but not limited to, a reticle, a photo-mask with or without a resist film being deposited thereon, and a wafer, which are subject to the formation of an ultrafine circuit pattern(s) for use in the manufacture of advanced ULSI semiconductor devices.
- a resist-formed photomask is used for purposes of convenience in discussion herein.
- the control unit 14 includes a system controlling computer 30 and a large-capacity data storage unit 32 which is operatively connected thereto.
- This storage 32 may function as a database (DB) that stores therein image data of ultrafine circuit patterns of high integration densities having minimum feature sizes on the order of magnitude of nanometers (nm).
- Storage 32 may also store other data, such as preset pattern writing conditions and various coefficients and constants for use in correction processes.
- the DB storage 32 may illustratively be a high speed-accessible large-capacity magnetic disk device.
- HDDs hard disk drives
- RAID redundant array of independent disks
- MO magneto-optic
- DVD next-generation digital versatile disk
- the control computer 30 includes a data input unit 34 which is connected to the storage 32 via a data transmission bus 36 .
- This input unit 34 is in turn connected to a draw image data processing unit 38 .
- This image data processor 38 is linked to a driver circuit 40 of the electron gun 20 in the above-noted pattern write unit 12 .
- the input unit 34 is also connected to a functional module 42 that is operable to determine through computation a proximity effect-corrected beam irradiation amount or dose and also to a serial combination of a function module 44 for calculating a proximity effect-corrected dose for exclusive use during fogging correction—say, fog correction-use proximity effect-corrected dose—and a function module 46 for calculation of a fog-corrected dose.
- the proximity effect-corrected dose calculator unit 42 and the fog-corrected dose calculator unit 46 are connected at their outputs to input nodes of a value combining unit 48 , respectively.
- This combiner 48 is illustratively a multiplier that functions to combine or “superpose” together the corrected dose values as output from the calculators 42 and 46 .
- Combiner 48 has its output connected to a shot time calculation unit 50 , which operates to calculate the real irradiation time of a charged particle beam—here, a shaped electron beam.
- the shot time calculator 50 has a built-in signal amplifier (not shown) and is connected to a circuit 52 for deflection control of the blanking deflector 22 in the pattern writing unit 12 .
- the function modules 44 to 50 for beam dose correction processing in the control computer 30 are arranged to have accessibility to a memory 54 by way of an internal data transfer bus 56 .
- each function module sends its calculation result to the memory 54 for temporary storage therein and reads data from this memory 54 .
- Memory 54 may typically be a semiconductor memory. Examples of it are a random access memory (RAM), electrically erasable and programmable read-only memory (EEPROM), “Flash” memory or functional equivalents thereto.
- the beam deflection control circuit 52 controls the deflector 22 in such a way as to appropriately deflect an electron beam 58 as emitted from the electron gun 20 to thereby guide it to fall onto each aimed location on the exposure surface of the photomask 28 being mounted on XY stage 26 , thereby writing a pattern of desired circuit shapes thereon.
- the respective calculators 42 to 50 of the control computer 30 is configurable from hardware components, such as electrical or electronics circuits. These hardware components may be replaced by software programs executable by digital computers or, alternatively, by firmware or any possible combinations thereof. The software programs are preinstalled to the magnetic disk device 32 or to a separate nonvolatile storage or recording unit which is functionally equivalent thereto. Some major examples include HDDs, magnetic tape devices, ROMs, PROMs, EEPROMs, and Flash memories.
- the electron beam 58 leaving the electron gun 20 is controlled so that its current density J is at a specified value.
- This beam 58 is deflected by the blanking deflector 22 under the control of deflection control circuit 52 in co-work with the system control computer 30 to pass through the hole of the blanking aperture plate 24 and then fall onto a desired position of the target workpiece 28 on XY stage 26 .
- a beam irradiation or “shoot” time has elapsed which permits the real beam dose on workpiece 28 to reach a prespecified level, it is a must to prevent excessive beam irradiation.
- the blanking deflector 22 deflects the electron beam 58 while the blanking aperture 24 blocks or “cuts off” the travelling of the beam to thereby ensure that beam 58 no longer reaches workpiece 28 .
- a deflection voltage of such deflector 22 is appropriately adjustable by the deflection controller 52 .
- the output electron beam 58 of the electron gun 20 travels to fall down almost vertically along an optical axis or “orbit” indicated by solid line in FIG. 1 .
- the “beam ON” period” a time period for allowing beam irradiation
- the “beam OFF” period” a time period for refusing beam shoot
- the electron beam 58 obliquely travels along an angled or “tilted” orbit indicated by dotted line 60 in FIG. 1 and thus is prevented by the blanking aperture plate 24 from further going ahead.
- no rays of this beam arrive at the workpiece 28 which lies under the aperture plate 24 .
- a variable-shaped beam (VSB) pattern generation system 70 as shown herein includes a charged particle source 72 , which may be an electron gun assembly. This system also includes a pair of vertically spaced beam-shaping aperture plates 74 and 76 .
- the upper aperture plate 74 has a rectangular opening or hole H 1 as defined therein.
- the lower aperture plate 76 has a rectangular hole H 2 .
- An electron beam 77 as output from the source 72 is guided to travel through a known illumination lens (not shown) and then reach upper aperture plate 74 .
- the beam passes through a known projection lens and a beam-shaping deflector (each not shown) and arrive at the lower aperture 76 .
- the resulting beam that is shaped in cross-section by the hole H 2 of aperture plate 76 is guided by an objective lens and objective deflector (not shown) to fall onto a target workpiece 28 a.
- the electron beam 77 leaving the gun 72 is guided to irradiate or “illuminate” a surface area of the upper aperture 74 which includes its rectangular hole H 1 . Passing through hole H 1 results in the beam being shaped to have a rectangular cross-sectional image. Resultant shaped beam 78 that passed through this aperture hole H 1 is projected onto the lower aperture 76 through the projection lens. A beam projection position on this aperture is controlled by the shaping deflector so that the beam is adequately changed both in shape and in size.
- the beam leaving the lower shaping aperture 76 is focussed by the objective lens and deflected by the objective deflector, whereby a focused beam spot is formed at a target position on workpiece 28 a .
- resist pattern size variations or fluctuations can occur due to the proximity effect and the fogging effect, resulting in undesired degradation of the uniformity of miniaturized linewidths on the workpiece surface, as has been discussed in the introductory part of the description.
- FIG. 3 shows in flowchart form a process 80 for computing a beam dose that is corrected both in proximity effect and in fogging effect in order to prevent or at least greatly suppress pattern size variations occurrable during pattern writing of the EBL apparatus 10 .
- the illustrative proximity effect/fogging-corrected beam dose computation procedure 80 starts with step 81 , which permits the control computer 30 in the system controller 14 of FIG. 1 to acquire circuit pattern image data from the storage 32 and receive the data at its data input unit 34 .
- This input unit passes or distributes ad libitum the pattern data among the image data processor 38 and the proximity effect-corrected dose calculator 42 plus the fogging effect correction-use proximity effect-corrected dose calculator 44 .
- step 82 causes the image data processor 38 to use the input pattern data to create beam shot data.
- step 83 calculate a beam irradiation time Tr at each shot on a real time basis.
- the driver circuit 40 is responsive to receipt of this beam irradiation time Tr to activate the electron gun 20 so that it emits an electron beam 58 for drawing or “writing” a pattern of mask shapes on a top surface of the target photomask 28 being processed.
- the procedure 80 enters a processing stage for correction of the proximity effect and the fogging effect.
- the proximity effect-corrected dose calculator 42 of FIG. 1 numerically determines through computation a corrected beam dose Dp(x,y) for correcting or “compensating” the proximity effect occurrable during mask pattern writing using the electron beam 58 .
- This proximity effect-corrected dose Dp(x,y) is obtainable by solving an integral equation (1) which follows:
- E is the radiation absorption quantity of the resist of the photomask 28 , which is a constant value.
- D(x,y) is the corrected beam dose
- ⁇ is the proximity effect correction coefficient
- ⁇ p (x,y) is the influence range of the proximity effect
- ⁇ is the fogging correction coefficient
- ⁇ f (x,y) is the influence range of fogging effect.
- the proximity effect-corrected dose Dp(x,y) thus calculated satisfies Equation (3) which follows:
- the proximity effect-corrected dose Dp(x,y) may be calculated using the constant value of absorption amount E which exhibits convergence in Equation (3) above, while involving therein higher orders of correction terms as indicated in Equations (4.1) to (4.4) below.
- n denotes the order number of a correction term.
- U(x,y) is the back-scatter amount standardized.
- the side length of each mesh region is defined by taking account of the fact that the influence range of the proximity effect is usually ten plus a few micrometers ( ⁇ m). As an example, let it be a square region with each side of 1 ⁇ m.
- the proximity effect-corrected dose Dp(x,y) is determined per each beam shot for execution of the intended correction.
- the per-shot proximity-corrected dose Dp(x,y) calculated in this way is stored in the memory 54 of FIG. 1 . It should be noted here that while the integration formula (1) above involves therein fogging effect parameters, separated execution of the proximity effect correction and the fogging effect correction speeds up the processing without lowering the accuracy.
- the system procedure 80 enters a stage 86 for executing numerical determination of the fogging effect-corrected beam dose Df(x,y).
- This process includes a sub-step S 1 of obtaining a fogging-corrected dose Df(x,y) as has been discussed in the introductory part of the description.
- Equation (2) the resist film's absorption is represented by:
- Equation (5) is given by:
- D f ⁇ ( x , y ) E E + ⁇ ⁇ ⁇ D p ⁇ ( x ′ , y ′ ) ⁇ ⁇ f ⁇ ( x - x ′ , y - y ′ ) ⁇ d x ′ ⁇ d y ′ .
- Equation (10) above suggests that the proximity effect-corrected dose Dp(x,y) as contained therein is to be subject to integral calculation over the extended influence range of the fogging effect.
- this calculation amount is drastically significant since the fogging effect's influence range is extraordinarily larger than the proximity-effect influence range as stated previously. This in turn makes it inevitable to take a much increased length of time to complete such arithmetical processing. Due to this, it must be concluded that mere direct calculation of the denominator of Equation (9) is impractical in view of the limited computer performance of the system controller 14 . Additionally the use of the above-noted approximation poses a risk as to unwanted occurrence of an unnegligible error (e.g., about 5%) in the fogging-corrected dose Df(x,y).
- an unnegligible error e.g., about 5%
- Equation (11) may be represented by:
- the fog-corrected dose Df(x,y) per fog correction mesh region with each side length of 1 mm makes it possible to greatly lessen the processing time in comparison with the above-noted straightforward calculation scheme.
- the advantage of this approach does not come without accompanying a penalty which follows. Due to the use of the fog correction mesh regions larger in size than those meshes for the proximity effect correction use, the resulting fog correction error becomes greater to an extent that is never acceptable in practical applications.
- the procedure 80 embodying this invention shown in FIG. 3 is arranged so that the proximity effect-corrected dose Dp(x,y) is set to a variable value rather than the fixed value over the influence range of the fogging effect.
- This variable proximity effect-corrected dose Dp(x,y) i.e., proximity effect-corrected dose Dpf(x,y) for exclusive use in the fog correction—is numerically determined through computation at a substep S 2 prior to the substep S 1 for fog-corrected dose calculation. This is one of the salient features unique to the illustrative embodiment.
- the procedure 80 goes to a preprocessing step in the fogging effect-corrected dose calculation step 86 —that is, substep S 0 of computing the value of a proximity effect-corrected dose Dpf(x,y) for exclusive use during the fogging effect correction.
- the “prestage” calculator 44 in upstream of the fogging-corrected dose calculator 46 of FIG. 1 calculates the fog correction-use proximity-corrected dose Dpf(x,y) that is variable in value upon execution of the integration calculation of the denominator of Equation (9), that is, Equation (10).
- Equation (10) To reduce or minimize the occurrable error of Equation (14), the integral calculation of Z(x,y) as shown in Equation (10) is executed at an adequate “coarse” that does not degrade the accuracy of fog correction.
- a practically implementable method of it is as follows.
- this mesh size is specifically determined to have a side length as large as possible while at the same time letting fog correction errors remain less enough to be negligible in practical applications.
- a plot line 90 is in a case where the fogging correction-use proximity effect-corrected dose Dpf(x,y) was calculated only for the least ordered term (i.e., zero-order term) of the proximity effect as indicated in Equation (4.2), whereas a plot 92 is in case the fog correction-use proximity-corrected dose Dpf(x,y) was computed up to a term of the third order of each of Equations (4.1) to (4.4).
- a difference between these cases in measured value change of fog correction errors is kept less and thus the lines 90 and 92 are very close to each other.
- the calculation involved is forced to be executed relative to the zero-order term only, with its higher order terms being excluded therefrom.
- a time taken for this calculation until the zero-order term is approximately 60% of that needed for an extensive calculation up to the third-order term.
- the fogging correction error in each case generally increases with an increase in mesh size for proximity effect correction.
- the fog correction error gradually increases.
- the mesh size exceeds 20 ⁇ m, its rate of increase becomes larger.
- the fog correction error rapidly grows so that it is no longer acceptable.
- the mesh size stays at a practically acceptable low level while it falls within a range of from 1 to 5 ⁇ m (this is about one-half of ⁇ ).
- the calculator 44 of FIG. 1 sets the mesh size of proximity effect-corrected dose Dp(x,y) to 5 ⁇ m.
- the influence distribution ⁇ p of proximity effect is not Gauss distribution, the mesh size may be set to about half the influence range.
- the fogging effect correction-use proximity effect-corrected dose calculator 44 sets the mesh size M 1 of a mesh region used for calculation of the fog correction-use proximity effect to a specific value which is midway between the fog correction mesh size M 2 and proximity effect correction mesh size M 2 of the pattern writing surface area of mask 28 —that is, at one-half (1 ⁇ 2) of ⁇ as equal to about 5 ⁇ m—and then calculates the fog correction-use proximity-corrected dose Dpf(x,y) in units of such specifically sized mesh regions.
- This dose calculation is done up to the zero-order term of its integration formula, with other terms of higher orders being intentionally excluded from the calculation.
- Respective values of per-mesh fog correction-use proximity-corrected dose Dpf(x,y) thus calculated in this way are stored in the internal memory 54 of control computer 30 .
- the calculator 46 reads the fogging correction-use proximity-corrected dose Dpf(x,y) being presently stored in the memory 54 and then uses it to compute the fog-corrected dose Df(x,y) that also contains therein the influence of the proximity effect during electron beam pattern drawing of the mask 28 .
- This fog-corrected dose Df(x,y) is calculable per fog correction mesh region having its intrinsic mesh size M 2 —here, 1 mm—in accordance with Equation (9) presented above.
- the resulting fog-corrected dose Df(x,y) calculated is stored in memory 54 .
- FIG. 5 is a graph showing some plot lines of fogging correction error versus “1:1 L/S” pattern linewidth characteristics.
- a plot line 94 indicates a change in fogging-corrected dose Df(x,y) as calculated under an assumption that the fog correction-use proximity-corrected dose Dpf(x,y) is constant within the integration region of Equation (10) shown in Equations (14.1) to (14.4).
- a plot line 96 indicates a change in fog-corrected dose Df(x,y) in the case where the fog correction-use proximity-corrected dose Dpf(x,y) is made variable in value and where calculations are performed up to the third order term of integral equation while setting the correction mesh size therefor to its intrinsic value, e.g., 1 ⁇ m.
- a curve 98 shows a change in fog-corrected dose Df(x,y) in case the mesh size M 1 of fog correction-use proximity-corrected dose Dpf(x,y) is increased to 5 ⁇ m and calculations are executed up to the integral equation's lowest order term, i.e., zero order term, with those calculations of its higher order terms being omitted.
- the fog-corrected dose calculator 46 is specifically arranged to execute computation of more than one term of higher order than the zero order term of the fogging-corrected dose Df(x,y). This computation is done using:
- D f ′′ ⁇ ( x , y ) - ⁇ ⁇ ⁇ D f 0 ⁇ ( x , y ) E ⁇
- FIG. 6 This shows how the fogging correction error varies relative to the integration order of fogging-corrected dose Df(x,y).
- this error change shows actual measured values when calculating up to the minimum or zero order term and those obtained when calculating up to the first order term in respective cases where the 1:1-L/S pattern linewidth is set to 1 ⁇ m, 32 ⁇ m, 64 ⁇ m, 128 ⁇ m, 256 ⁇ m and 512 ⁇ m.
- execution of the calculation processing up to the integral term of higher order than the least significant order results in the fog correction error being noticeably reduced.
- the fog correction error due to the above-noted approximation is inherently as small as 0.14% or below and thus a difference relative to the case of the higher order term being also subjected to the computation is without particular distinction; however, if the “up-to-higher-order calculation” feature of this embodiment is applied to rectangular pattern shapes, it is expectable to attain distinctive improvements of 5% or more in reduction of fog correction errors.
- the fogging effect-corrected dose calculator 46 is designed to calculate the fogging-corrected dose Df(x,y) that contains an integration term of higher order than the least significant (zero) order term thereof, thereby to ensure further lessening of the resultant fog correction error.
- the procedure 80 goes next to step 87 .
- the corrected dose value combiner 48 reads out of the memory 54 both the proximity effect-corrected dose Dp(x,y) and the fogging-corrected dose Df(x,y) being presently stored therein, and then combines them together by multiplication to thereby determine a total or “final” beam dose D(x,y). More precisely, calculate a product of the proximity effect-corrected dose Dp(x,y) and fogging-corrected dose Df(x,y) in accordance with Equation (2).
- the write beam dose D(x,y) calculated is stored in the memory 54 .
- the control computer 30 generates at its output a signal indicative of this irradiation time Tr, which is passed to the deflection control circuit 52 that is associated with the blanking deflector 22 in pattern writing unit 12 .
- the deflection controller 52 is responsive to receipt of the output signal of control computer 30 , for providing operation control of the blanking deflector 22 in a way such that the electron beam 58 which is writing a pattern on the mask 28 is deflected and turned off after elapse of the irradiation time Tr thus defined.
- the beam is controlled to hit mask 28 with the optimal dose D so that a desired mask pattern is drawn on its surface and, thereafter, beam 58 is deflected by deflector 22 to change its traveling route or “orbit” whereby it is blocked by the blanking aperture plate 24 so that the beam no longer reaches mask 28 .
- the desired circuit pattern is written on mask 28 while performing calculations of the proximity effect-corrected dose Dp(x,y) and fogging-corrected dose Df(x,y) in a parallel way to the progress of fabrication process—that is, while performing the proximity-effect/fogging correction on a real time basis.
- the fogging-corrected dose Df(x,y) per se takes account of the influence of the proximity effect.
- the proximity effect-corrected dose Dpf(x,y) for specific use in the course of calculating the fogging-corrected dose Df(x,y) is computed as an adequate variable value in a case-sensitive way without assuming (approximating) it to be a fixed value within the integration region of fog-corrected dose computation.
- the calculation of the fog correction-use proximity-corrected dose Dpf(x,y) is such that its mesh size M 1 is set smaller than the mesh size M 2 inherent to the fogging-corrected dose Df(x,y) and yet larger than the mesh size M 3 of the proximity effect-corrected dose Dp(x,y).
- M 1 the mesh size of the fog correction-use proximity-corrected dose
- M 3 the mesh size of the proximity effect-corrected dose
- the mesh size M 2 in the calculation of the fogging-corrected dose Df(x,y) is about 1 mm as usual, and the mesh size M 3 of proximity effect-corrected dose Dp(x,y) is at 1 ⁇ m.
- a further advantage of this embodiment is as follows.
- the calculator 44 in control computer 30 is arranged to compute, upon calculation of the fogging correction-use proximity-corrected dose Dpf(x,y), only the zero order term, i.e., the term of the least significant order, while intentionally excluding its higher order terms from the computation. This makes it possible to minimize or at least greatly suppress the calculation amount without lowering the required correction accuracy to an extent that it departs from the practically allowable range. Thus it is possible to shorten the calculation time.
- the fogging effect-corrected dose calculator 46 is configured to calculate the fogging-corrected dose Df(x,y) while letting more than one higher order term than its lowest order term be involved therein.
- the fog correction error of about 5%, which unavoidably occurs in the currently established approach—i.e., the technique for applying the above-stated presumption (approximation) of the Df value being at a fixed value within the integration region of Equation (7). This in turn brings further improvement of the multiple irradiation effect correction accuracy.
- FIG. 7 an entire system configuration of a shaped electron beam lithographic (EBL) apparatus 10 a also embodying this invention is shown.
- This EBL tool 10 a is similar to that shown in FIG. 1 with the fogging effect correction-use proximity effect-corrected dose calculator 44 and the fog-corrected dose calculator 46 in control computer 30 being replaced by their functionally equivalent fogging effect correction-use proximity effect-corrected dose calculator 44 a and fog-corrected dose calculator 46 a which are built in an externally linkable server equipment 100 , and also with a map data storage unit 102 being added to the computer 30 .
- the EBL tool 10 is arranged to calculate the fogging-corrected dose Df(x,y) on a real-time basis in a parallel way to the pattern writing on photomask 28
- the EBL tool 10 a of FIG. 7 operates in a way such that the fogging-corrected dose Df(x,y) has already been calculated prior to the pattern drawing session.
- Resultant map data indicative of fogging-corrected dose values in units of square mesh regions with each side of 1 mm, for example, are prestored in the map storage 102 . During pattern writing, access is given thereto to read this map data, and use this data to perform the beam dose correction required.
- the system controller 14 includes a control computer 30 a .
- This computer is operatively connected to its externally associated server computer 100 .
- This server may illustratively be a workstation or a high-performance personal computer (PC) or like computers.
- the server 100 has its built-in fogging effect correction-use proximity effect-corrected dose calculator 44 a and fogging-corrected dose calculator 46 a , wherein the former is connected to the magnetic disk device 32 such as HDD in controller 14 whereas the latter is coupled via a known interface (not shown) to the map storage 102 as internally provided in the control computer 30 a .
- Map storage 102 is connected to a storage controller 104 that functions to manage data reading from storage 102 .
- Map-format data as read out of storage 102 under control of the data manager 104 this data is representative of the precalculated fogging-corrected dose Df(x,y)—will then be sent forth to the corrected dose combiner 48 , which may be a multiplier.
- FIG. 8 shows a flow diagram of a method for determining through computation the dose of a shaped electron beam 58 which is corrected in its related proximity effect and fogging effect occurring during circuit pattern writing on a workpiece 28 , which is illustratively a photomask.
- a system procedure 80 a as shown herein is essentially similar to that of FIG. 3 with the steps 86 and 87 being replaced by a step 106 .
- the procedure 80 a goes to step 106 .
- the storage manager 104 provides access to the map storage 102 .
- This storage stores in a map form the per-mesh fogging effect-corrected dose Df(x,y) as has been computed in advance by the external server 100 .
- Data indicative of the fog-corrected dose as read from storage 102 is then passed to the corrected dose combiner 48 under control of manager 104 .
- Combiner 48 combines or multiplies this fog-corrected dose to the proximity effect-corrected dose Dp(x,y) as output from the proximity-corrected dose calculator 42 to generate at its output a combined corrected dose D(x,y), which is then sent to the deflection controller 52 .
- the following operations are similar to those in the previous embodiment.
- the beam dose that is corrected in the fogging effect occurrable during pattern writing on the mask 28 is not calculated on a real-time basis but is computed in advance by the external associative server 100 prior to startup of the pattern writing, the data of which is prepared in the internal storage 102 of the control computer 30 a .
- Using such precomputed fog-corrected dose allows the control computer 30 a to become free from the burden to compute the dose at any time whenever it is required. Accordingly the calculation tasks in entirety of the EBL tool 10 a are reduced, thereby making it expectable to increase the throughput of pattern writing processing.
- This system calculation function relocation or “transplantation” feature is devoted to further improvements in speed performance of the EBL system en masse.
- control computer 30 , 30 a are implemented by several hardware components as shown in FIGS. 1 and 7 , these may be replaceable with a set of software program modules executable by general-purpose computers.
- a “hybrid” system with hardware and software combinations may be employed. Its part or entirety is designable to use firmware configurations.
- the software program(s) is/are contained in one or more computer-installable recording media with storability or recordability of increased stability.
- CD-ROM compact disc read-only memory
- DVD digital versatile disk
- HD-DVDTM high-DVDTM
- Blu-ray DiscTM portable external HDD equipment and equivalents thereto.
- the invention should not exclusively be limited thereto and may alternatively be applicable to systems of the type using other kinds of energy radiation beams without requiring any inventive activities.
- energy radiation include, but not limited to, light rays, X-rays, ion beams, and extreme-ultraviolet (EUV) radiation.
- EUV extreme-ultraviolet
- the workpiece being subjected to pattern writing/exposure this is not limited to the photomask and may alternatively be other similar structures, such as reticles, wafers, membranes, substrates or like structures.
- the write beam dose calculation technique incorporating the principles of this invention is employable for purposes other than the direct formation of a resist circuit pattern on workpieces, including fabrication of masks for use with light-stepper equipment and X-ray masks by way of example.
- the mesh size M 1 therefor is set to the specific value that is half the influence range ⁇ (e.g., 5 ⁇ m), this is a mere typical example and is not to be construed as limiting the invention. Its value may be changed on a case-by-case basis insofar as M 1 is between M 2 and M 3 . If the computer employed is of extra-high performance and affords to have additional task-processing abilities, then M 1 may be set at further less values. On the contrary, if processing time shortening is the top priority, it is permissible to set M 1 to be substantially the same as ⁇ or, alternatively, to a twofold value thereof.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Nanotechnology (AREA)
- Physics & Mathematics (AREA)
- Crystallography & Structural Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Manufacturing & Machinery (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- Analytical Chemistry (AREA)
- Electron Beam Exposure (AREA)
Abstract
Description
D(x,y)=D p(x,y)D f(x,y), (2)
where Df(x,y) is the fogging-corrected beam dose, and Dp(x,y) is the proximity effect-corrected dose. The proximity effect-corrected dose Dp(x,y) thus calculated satisfies Equation (3) which follows:
As the influence range of the fogging is several millimeters (mm) to several centimeters (cm) and is extraordinarily wider, beyond orders of magnitude, than the proximity effect's influence range of about ten-odd μm as stated previously, the value Df(x,y) is deemed to stay constant in the integration of the second term in the right-side part of Equation (5). As a consequence, Equation (5) is given by:
From this Equation (6) and the above-identified Equation (3), we obtain:
E=D f(x,y)E+θ∫D p(x′,y′)D f(x′,y′)κf(x−x′,y−y′)dx′dy′. (7)
E=D f(x,y)└E+θ∫D p(x′,y′)κf(x−x′,y−y′)dx′dy′┘. (8)
Thus, the fogging-corrected dose Df(x,y) is given as:
To obtain the fog-corrected dose Df(x,y), an attempt may be done to execute the integration of denominator part of Equation (9). More specifically, perform integral calculation processing of:
Z(x,y)=∫D p(x′,y′)κf(x−x′,y−y′)dx′dy′. (10)
Putting Equation (12) into Equation (11), the fogging-corrected dose Df(x,y) is given by:
This equation is in turn expressed as:
V(x,y)=∫κf(x−x′,y−y′)dx′dy′. (14.2)
-
- proximity effect (PE) correction coefficient: η=0.6
- fogging effect (FE) correction coefficient: θ=0.1
- PE influence range κp: Gauss distribution with σ=10 μm
- FE influence range κf: Gauss distribution with σ=1 cm.
In the discussion below, these parameter values will be employed except as otherwise indicated.
where “n” is the order or degree of correction term.
Tr=D(x,y)/J·Dref, (16)
where J is the beam current density, and Dref is the reference irradiation amount. The
Claims (17)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2006036639A JP4773224B2 (en) | 2006-02-14 | 2006-02-14 | Charged particle beam drawing apparatus, charged particle beam drawing method and program |
JP2006-036639 | 2006-02-14 |
Publications (2)
Publication Number | Publication Date |
---|---|
US20070187624A1 US20070187624A1 (en) | 2007-08-16 |
US7525110B2 true US7525110B2 (en) | 2009-04-28 |
Family
ID=38367430
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/671,789 Active 2027-09-28 US7525110B2 (en) | 2006-02-14 | 2007-02-06 | Multiple irradiation effect-corrected dose determination technique for charged particle beam lithography |
Country Status (3)
Country | Link |
---|---|
US (1) | US7525110B2 (en) |
JP (1) | JP4773224B2 (en) |
KR (1) | KR100843918B1 (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110033788A1 (en) * | 2009-08-04 | 2011-02-10 | Nuflare Technology, Inc. | Charged particle beam drawing apparatus and method |
US8309283B2 (en) | 2009-01-06 | 2012-11-13 | Nuflare Technology, Inc. | Method and apparatus for writing |
US20120292535A1 (en) * | 2011-05-18 | 2012-11-22 | Jin Choi | Exposure systems for integrated circuit fabrication |
US8352889B2 (en) | 2005-10-25 | 2013-01-08 | Nuflare Technology, Inc. | Beam dose computing method and writing method and record carrier body and writing apparatus |
US8539392B2 (en) | 2011-02-24 | 2013-09-17 | National Taiwan University | Method for compensating proximity effects of particle beam lithography processes |
US20140017349A1 (en) * | 2012-07-10 | 2014-01-16 | Nuflare Technology, Inc. | Charged particle beam writing apparatus and irradiation time apportionment method of charged particle beams for multiple writing |
US20150041684A1 (en) * | 2013-08-08 | 2015-02-12 | Nuflare Technology, Inc. | Charged particle beam writing apparatus and charged particle beam writing method |
US9535327B2 (en) | 2011-03-31 | 2017-01-03 | Nuflare Technology, Inc. | Method for fabricating semiconductor device, pattern writing apparatus, recording medium recording program, and pattern transfer apparatus |
Families Citing this family (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7619230B2 (en) * | 2005-10-26 | 2009-11-17 | Nuflare Technology, Inc. | Charged particle beam writing method and apparatus and readable storage medium |
JP5069052B2 (en) * | 2007-07-30 | 2012-11-07 | 日本電子株式会社 | Dose correction method and charged particle beam drawing apparatus |
JP5134944B2 (en) | 2007-12-27 | 2013-01-30 | 株式会社ニューフレアテクノロジー | Drawing apparatus and drawing method |
JP5480496B2 (en) * | 2008-03-25 | 2014-04-23 | 株式会社ニューフレアテクノロジー | Charged particle beam drawing method and charged particle beam drawing apparatus |
US8062813B2 (en) | 2008-09-01 | 2011-11-22 | D2S, Inc. | Method for design and manufacture of a reticle using a two-dimensional dosage map and charged particle beam lithography |
US8669023B2 (en) | 2008-09-01 | 2014-03-11 | D2S, Inc. | Method for optical proximity correction of a reticle to be manufactured using shaped beam lithography |
US7901850B2 (en) | 2008-09-01 | 2011-03-08 | D2S, Inc. | Method and system for design of a reticle to be manufactured using variable shaped beam lithography |
US7799489B2 (en) * | 2008-09-01 | 2010-09-21 | D2S, Inc. | Method for design and manufacture of a reticle using variable shaped beam lithography |
US20120219886A1 (en) | 2011-02-28 | 2012-08-30 | D2S, Inc. | Method and system for forming patterns using charged particle beam lithography with variable pattern dosage |
US8017286B2 (en) * | 2008-09-01 | 2011-09-13 | D2S, Inc. | Method for design and manufacture of a reticle using a two-dimensional dosage map and charged particle beam lithography |
US8057970B2 (en) | 2008-09-01 | 2011-11-15 | D2S, Inc. | Method and system for forming circular patterns on a surface |
US9323140B2 (en) | 2008-09-01 | 2016-04-26 | D2S, Inc. | Method and system for forming a pattern on a reticle using charged particle beam lithography |
US8017288B2 (en) * | 2008-09-01 | 2011-09-13 | D2S, Inc. | Method for fracturing circular patterns and for manufacturing a semiconductor device |
US9341936B2 (en) | 2008-09-01 | 2016-05-17 | D2S, Inc. | Method and system for forming a pattern on a reticle using charged particle beam lithography |
DE102008053180B4 (en) * | 2008-10-24 | 2012-07-12 | Advanced Mask Technology Center Gmbh & Co. Kg | Particle beam writing method, particle beam writing apparatus and maintenance method for the same |
US9164372B2 (en) | 2009-08-26 | 2015-10-20 | D2S, Inc. | Method and system for forming non-manhattan patterns using variable shaped beam lithography |
JP5525798B2 (en) * | 2009-11-20 | 2014-06-18 | 株式会社ニューフレアテクノロジー | Charged particle beam drawing apparatus and method for correcting charging effect thereof |
JP5547567B2 (en) * | 2010-06-30 | 2014-07-16 | 株式会社ニューフレアテクノロジー | Charged particle beam drawing apparatus and control method thereof |
JP5924043B2 (en) * | 2011-09-30 | 2016-05-25 | 凸版印刷株式会社 | Backscatter correction device, backscatter correction method, and backscatter correction program |
JP6087154B2 (en) | 2013-01-18 | 2017-03-01 | 株式会社ニューフレアテクノロジー | Charged particle beam drawing apparatus, method of adjusting beam incident angle on sample surface, and charged particle beam drawing method |
USD759603S1 (en) | 2013-07-17 | 2016-06-21 | Nuflare Technology, Inc. | Chamber of charged particle beam drawing apparatus |
US9984853B2 (en) | 2014-11-28 | 2018-05-29 | Nuflare Technology, Inc. | Method for generating writing data |
JP2016184605A (en) | 2015-03-25 | 2016-10-20 | 株式会社ニューフレアテクノロジー | Charged particle beam drawing device and drawing date creation method |
JP6679933B2 (en) * | 2016-01-05 | 2020-04-15 | 株式会社ニューフレアテクノロジー | Drawing data creation method |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH11204415A (en) | 1998-01-19 | 1999-07-30 | Toshiba Corp | Method and device for electron beam drawing |
US6783905B2 (en) * | 2001-12-27 | 2004-08-31 | Samsung Electronics Co., Ltd. | Electron beam exposure method using variable backward scattering coefficient and computer-readable recording medium having thereof |
JP3680425B2 (en) | 1996-06-19 | 2005-08-10 | ソニー株式会社 | Photomask manufacturing method and method for determining electron beam irradiation correction amount for resist material |
US7241542B2 (en) * | 2004-06-29 | 2007-07-10 | Leica Microsystems Lithography Gmbh | Process for controlling the proximity effect correction |
US7435517B2 (en) * | 2004-06-29 | 2008-10-14 | Vistec Electron Beam Gmbh | Method for reducing the fogging effect |
Family Cites Families (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US297025A (en) * | 1884-04-15 | Mail-bag | ||
US294263A (en) * | 1884-02-26 | Amalgamator | ||
JPH05335222A (en) * | 1992-05-29 | 1993-12-17 | Fujitsu Ltd | Electron-beam exposure device |
JP2647000B2 (en) * | 1994-05-25 | 1997-08-27 | 日本電気株式会社 | Electron beam exposure method |
JPH0915866A (en) * | 1995-06-30 | 1997-01-17 | Nikon Corp | Pattern transfer method and transfer device by charged particle beam |
JP2001109128A (en) * | 1999-10-12 | 2001-04-20 | Hitachi Ltd | Pattern data forming method for lithography and method for manufacturing semiconductor device and apparatus for manufacturing semiconductor device using the same |
JP3952736B2 (en) * | 2001-10-25 | 2007-08-01 | ソニー株式会社 | Exposure method |
JP4189232B2 (en) * | 2002-02-08 | 2008-12-03 | 株式会社東芝 | Pattern forming method and drawing method |
JP3725841B2 (en) * | 2002-06-27 | 2005-12-14 | 株式会社東芝 | Electron beam exposure proximity effect correction method, exposure method, semiconductor device manufacturing method, and proximity effect correction module |
JP2004140311A (en) * | 2002-08-20 | 2004-05-13 | Sony Corp | Exposure method and aligner |
US7592103B2 (en) * | 2004-03-31 | 2009-09-22 | Hoya Corporation | Electron beam writing method and lithography mask manufacturing method |
JP4101247B2 (en) * | 2004-03-31 | 2008-06-18 | Hoya株式会社 | Electron beam drawing method, lithography mask manufacturing method, and electron beam drawing apparatus |
JP4607623B2 (en) * | 2005-03-03 | 2011-01-05 | 日本電子株式会社 | Electron beam writing method and apparatus |
-
2006
- 2006-02-14 JP JP2006036639A patent/JP4773224B2/en active Active
-
2007
- 2007-02-06 US US11/671,789 patent/US7525110B2/en active Active
- 2007-02-13 KR KR1020070014615A patent/KR100843918B1/en active IP Right Grant
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3680425B2 (en) | 1996-06-19 | 2005-08-10 | ソニー株式会社 | Photomask manufacturing method and method for determining electron beam irradiation correction amount for resist material |
JPH11204415A (en) | 1998-01-19 | 1999-07-30 | Toshiba Corp | Method and device for electron beam drawing |
US6783905B2 (en) * | 2001-12-27 | 2004-08-31 | Samsung Electronics Co., Ltd. | Electron beam exposure method using variable backward scattering coefficient and computer-readable recording medium having thereof |
US7241542B2 (en) * | 2004-06-29 | 2007-07-10 | Leica Microsystems Lithography Gmbh | Process for controlling the proximity effect correction |
US7435517B2 (en) * | 2004-06-29 | 2008-10-14 | Vistec Electron Beam Gmbh | Method for reducing the fogging effect |
Non-Patent Citations (2)
Title |
---|
U.S. Appl. No. 11/460,848, filed Jul. 28, 2006, Keiko Emi, et al. |
U.S. Appl. No. 11/535,725, filed Sep. 27, 2006, Junichi Suzuki, et al. |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8352889B2 (en) | 2005-10-25 | 2013-01-08 | Nuflare Technology, Inc. | Beam dose computing method and writing method and record carrier body and writing apparatus |
US8309283B2 (en) | 2009-01-06 | 2012-11-13 | Nuflare Technology, Inc. | Method and apparatus for writing |
US20110033788A1 (en) * | 2009-08-04 | 2011-02-10 | Nuflare Technology, Inc. | Charged particle beam drawing apparatus and method |
US8481964B2 (en) * | 2009-08-04 | 2013-07-09 | Nuflare Technology, Inc. | Charged particle beam drawing apparatus and method |
US8539392B2 (en) | 2011-02-24 | 2013-09-17 | National Taiwan University | Method for compensating proximity effects of particle beam lithography processes |
US9535327B2 (en) | 2011-03-31 | 2017-01-03 | Nuflare Technology, Inc. | Method for fabricating semiconductor device, pattern writing apparatus, recording medium recording program, and pattern transfer apparatus |
US8563951B2 (en) * | 2011-05-18 | 2013-10-22 | Samsung Electronics Co., Ltd. | Exposure systems for integrated circuit fabrication |
US20120292535A1 (en) * | 2011-05-18 | 2012-11-22 | Jin Choi | Exposure systems for integrated circuit fabrication |
US20140017349A1 (en) * | 2012-07-10 | 2014-01-16 | Nuflare Technology, Inc. | Charged particle beam writing apparatus and irradiation time apportionment method of charged particle beams for multiple writing |
US9141750B2 (en) * | 2012-07-10 | 2015-09-22 | Nuflare Technology, Inc. | Charged particle beam writing apparatus and irradiation time apportionment method of charged particle beams for multiple writing |
US20150041684A1 (en) * | 2013-08-08 | 2015-02-12 | Nuflare Technology, Inc. | Charged particle beam writing apparatus and charged particle beam writing method |
US9837247B2 (en) * | 2013-08-08 | 2017-12-05 | NuFlare Technology Co., Inc. | Charged particle beam writing apparatus and method utilizing a sum of the weighted area density of each figure pattern |
US10199200B2 (en) | 2013-08-08 | 2019-02-05 | Nuflare Technology, Inc. | Charged particle beam writing apparatus and charged particle beam writing method |
US10381194B2 (en) | 2013-08-08 | 2019-08-13 | Nuflare Technology, Inc. | Charged particle beam writing apparatus and charged particle beam writing method |
Also Published As
Publication number | Publication date |
---|---|
KR20070082030A (en) | 2007-08-20 |
KR100843918B1 (en) | 2008-07-04 |
JP4773224B2 (en) | 2011-09-14 |
JP2007220728A (en) | 2007-08-30 |
US20070187624A1 (en) | 2007-08-16 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US7525110B2 (en) | Multiple irradiation effect-corrected dose determination technique for charged particle beam lithography | |
US7740991B2 (en) | Beam dose computing method and writing method and record carrier body and writing apparatus for determining an optimal dose of a charged particle beam | |
US7669174B2 (en) | Pattern generation method and charged particle beam writing apparatus | |
US8309283B2 (en) | Method and apparatus for writing | |
US7511290B2 (en) | Charged particle beam writing method and apparatus | |
US7662522B2 (en) | Method for manufacturing semiconductor devices, and method for forming a pattern onto an exposure mask | |
US7750324B2 (en) | Charged particle beam lithography apparatus and charged particle beam lithography method | |
US8429575B2 (en) | Method for resizing pattern to be written by lithography technique, and charged particle beam writing method | |
US8552405B2 (en) | Charged particle beam writing apparatus and charged particle beam writing method | |
US7608845B2 (en) | Charged particle beam writing apparatus and method thereof, and method for resizing dimension variation due to loading effect | |
US8791432B2 (en) | Charged particle beam writing apparatus and charged particle beam writing method | |
US20140138527A1 (en) | Charged particle beam writing apparatus and charged particle beam dose check method | |
US9018602B2 (en) | Charged particle beam writing apparatus and charged particle beam writing method | |
JP3466900B2 (en) | Electron beam writing apparatus and electron beam writing method | |
US8487281B2 (en) | Electron beam exposure apparatus and electron beam exposure method | |
US8759799B2 (en) | Charged particle beam writing apparatus and charged particle beam writing method | |
JP2001052999A (en) | Charged particle beam exposure method | |
US10950413B2 (en) | Electron beam irradiation method, electron beam irradiation apparatus, and computer readable non-transitory storage medium | |
US11456153B2 (en) | Charged particle beam writing method and charged particle beam writing apparatus | |
US11443918B2 (en) | Charged particle beam writing method and charged particle beam writing apparatus | |
US9117632B2 (en) | Charged particle beam writing apparatus and charged particle beam writing method | |
JP5401135B2 (en) | Charged particle beam drawing method, charged particle beam drawing apparatus and program |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: NUFLARE TECHNOLOGY, INC., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SUZUKI, JUNICHI;EMI, KEIKO;ABE, TAKAYUKI;REEL/FRAME:018859/0457;SIGNING DATES FROM 20070118 TO 20070127 |
|
STCF | Information on status: patent grant |
Free format text: PATENTED CASE |
|
CC | Certificate of correction | ||
FPAY | Fee payment |
Year of fee payment: 4 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 8 |
|
MAFP | Maintenance fee payment |
Free format text: PAYMENT OF MAINTENANCE FEE, 12TH YEAR, LARGE ENTITY (ORIGINAL EVENT CODE: M1553); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY Year of fee payment: 12 |